Automatic steering apparatus



July 2o, 1943. N, T SAWDEY 2,324,882

AUTOMATIC lSTEERING APPARATUS Filed Oct. 18,- 1941 l 5 Sheets-Sheet 1 A Tronw: Y

July 20, 1943. N, T, SAWDEY l2,324,882

AUTOMATI C STEERING APPARATUS Filed Oct. 18, 1941 5 Sheets-Sheet 2 2 437? -E l V 43h l l f 'lll/Il /N VEN To R.- NE/z. 7. SA WDEY ATTORNEY July 20, 1943'. N. fr. sAwDr-:Y

l AUTOMATIC STEERING APPARATUS 5 Sheets-Sheet 5 Filed Oct. 18, 1941 2/NvEN-ron: NEI/ 7.' AwoEY BY LQM ATTORNEY July 20, 1943. N. T. sAwDEY AUTOMATIC STEERING APPARATUS Filed ot. 18, r1941 5 sheets-sheet 4 /NvEN-ran: NE1L `Z' SA wDEY BYaW-ru/ a/m Avro/#wax July-2o, 1943. N. T. SAWDEY 2,324,882

AUTOMATIC STEERING APPARATUS Filed Oct. 18, 1941 5 Sheets-Sheet 5 i4 BY/ZML/ l/m i5 ATToA/EY Patented July 20, 1943 UNITEDk STATES, PATENT OFFICE AUTOMATIC STEERING APPARATUS Neil T. sawdey, shaker Heights, ohio A Application October 18, 1941,.Scrial No. 415,543

Y 15 claims. lol. 114-144) This invention relates to automatic steering mechanism for vessels. While not limited to any .particular class o1- size, it Vaims particularly to provide automatic steering apparatuscharacterized by simplicity and compactness, `capable of manufacture in a price range available for small moderate priced pleasure and commercial craft,

y the invention being easy to attach to boats already built, simple to operate, not likelyto get out of order, readily serviced and repaired, and

requiring only slight power. f

Other purposes and advantages ol? my inven ,tion will be apparent from the following description of a preferred form, it being understood that i such 'preferred form, illustrated and described in detail, does not exclude the application of the principles of my invention in other specific emibodiments.

Although primarily intended for water vessels,

I and described as applied thereto, the scope of use of my invention is not so limited. It may be employed for the automatic steering of any moving apparatus to which its characteristics make it applicable.

In the accompanying drawings:

Fig. l is an elevation with some parts broken away, taken athwartships and looking forward,

` showing a typical installation;

- but showing successive positions in the operating cycle;

Fig. 9 is an enlarged perspective detail of certain elements from Figs. to 8, but looking aft; Fig. 10 is a further enlarged perspective detail from Fig. 9, looking in the same direction as in Fig. 9;

Fig. 11 is a Wiring diagram;

Fig. l2 is a fore-and-aft section through the.

compass and its mounting, as indicated by line I2-I2 of Fig. 14, looking lin the direction of the Fig. 13 is a fragmentary' horizontal section indicated by line I3--I3 of Fig. 12,V showing a detail of one of the feeler'nger mountings which is broken away in Fig. 14;

Fig. 14 is a horizontal section, with partsin elevation, approximately as indicated by line III- I4 of Fig. 12,- but with certain mounting details brokenaway;

Fig. 15 is an irregular broken` section, as indicated by line I5-I 5 of Fig. 14, in the direction of the arrows; and

Figs. 16 to 20 are diagrams which correspond generally to Fig. 5 and show relative positions of the electrical controls in various stages of the steering action. Y

Throughout the specification and claims the terms right and left, or R and L as parts of reference charactersare used with respect to rudder movements caused by the various elements so indicated; and the mechanism shown in General arrangement and operation The automatic steerer consists in general of two parts, Fig. 1; namely, the control unit and the Vcompass unit II. The control unit, Figs. 1

` to 10, is connected to the steering wheel shaft I2 and so controls the movement of vthe'rudde'nthe direction and amount of this movement being determined bythe vcompass unit, Figs. 13 to 16.

n In a typical installation the control unit is in a housing I3 suitably mounted, as for example on a transverse bulkhead. The compass unit II is vmounted in some convenient location :away from magnetic disturbances and within reach of the helmsmans station. Connection may con- X veniently be made from the compass unit to the ingvessel it may be necessary to increase the length of the steering shaft I2.

Briefly stated, the operation is that the control unit makes corrective responses to the position of the vessels head, such position being determined at frequent intervals by a feeler system (Fig. 15) in the compass unit II. The compass unit is set by hand to the desired course, power is switched on to the steeringmotor I6 and control motor Worm gear 22. mounting the drive shaft 2i! in rbearings 29 and -fBIJ'on a plate 3I 'which is pivoted at 32 near its lower end", and guided-at 33 near the top. Spring Control unit As shown in Fig. 1, the steering motor I6 is connected by reduction gearing to drive shaft 20 and through a worm 2| on that lshaft to a worm i gear 22 on the steering shaft I2, the shaft I2 being connected to the rudder by any suitable means, not illustrated. A chain 23, kept vtautliy an idler 24, transmits power from a sprocket'ZS l,

fast on shaft I2 just forward of the hand steering f. wheel 26 to another sprocket 2`I fast to a pinion 28 which is a part of the steering motor controls -described 3further on. -Thesprocket 21- may be interchangeable `in several siaes.

To throw out the'automatic mechanism and allow manual steering, the shift leverIS is moved to the'right,'disconn`ectingfthe Worm 2| from the A preferred arrangement is by `34 normally holds 'worm 2l engaged with Worm gear 22. A notch 35 or other'suitable device f latchesthe parts in hand-steering position. VSteering motor controls, Figs.i 1 and 4 to 10, in-

elusive -Thel general principle of this part of the mechanis'm is that'of having a switch-arm 40 move `olv'er contact segments 4I, 42 and 43 in response to thecmpass position when `the vessel leaves her course, thereby actuating the steering motor I6 which moves the rudder. Then as the ship swings back to Athe course -the Contact segments make a corresponding movement under the v f switch 'arm tocutpower'off the steering motor.

The kdetails offthe 'compassunit mechanism are described hereafter, lbut for the purpose of underv'standing the steering action it is'here noted that Ythe compass unit includes a" pair of scissors-like il 'feelers44j45 to which a closing and opening mojtion is imparted at intervals by the control motor I1 through compass pull rod 4I5 and other connections. v'Apointer 46 on the -compass swings bej-tween these feelers and is caught by them on l their closing movement, and stops such closing A"movement-'at a more orless complete stage ac- "co'rdingito the'position' of the pointer. The extent ofl closing, which indicates whether the vessel is on course or how'much and in which direcltion 'oii'is'refiected in the 'position ofthe switch yarm 40.

The switching mechanism comprises a system of arms, levers and links,'principailyswinging on pinto. The system is actuated by the'control Amotor I 1, together withcertain other related elel ments. As will best beseen in Fig. 4,'the pin`50,

which is horizontally'xed'tothe housing I3 or tol 'dead s'pace"4`3D, all on an outer radius.

ipitman GI- or other suitable connection. Idown stroke (counterclockwise) of this bell crank the forward wall of the housing I3, but oiset therefrom to permit the segment arm 5I to swing beneath it, and a guide bar 4IA may be used to hold segment arm 5I against forward thrust. Electrical contact segments MR and IIIL, with a dead element 4ID between them, are secured to segment 4I.

The segment arm 5I is toothed at its upper end at 5IA for movement by pinion 28 simultaneously with movement of the steering shaft I2, and in the opposite direction to the rudder. The ratio of motion between I2 and 5I depends upon the size of the sprocket used. Arm 5| carries a cross piece 5IB with two concentric sets of electrical "contactv segments, namely 42R and 42L with a middlefspacej42D, all on an inner radius, and 43B and 43L with a proportionately longer middle The switch arm 40 swings over the stationary and movable segments, carrying three brushes or wiping contacts 4IC, y42C and 43C aligned respectively with each series of contact segments. Brushes 4IC` and 42C are electrically connected by a bar |30. Wiring is shown-only in Fig. 11.

The remainder of this mechanism can beist'be described along with a partial description of its l action. The control motorvl (Fig. 1) constantly oscillates a 'bell crank 60 through a crank and The pulls 62 to the right, compressing a spring 62A against a fixed lug 62B. The latter part of the same strike also closes a limit switch `IiiZI, as indicated by the dotted line positions of Figs. 1 and "11, for purposes explained hereafter under the heading Electrical system.

The pull of rod 62 breaks toggle 63 to the right, Fig. 8. The upper arm of the toggle is the keeper 53, a centrallyepivoted lever whose upperV end includes a side finger V53A projecting aft far enough to engage'the left edge of the locking arm i4,l*ig.' 6. Pull rod I5 is pivoted to a side branch v54A of the locking arm. A compression spring 64 bears at its upper end on a lug 65 fast to the forward wall ofthe housing I 3, and bears downward at its lower end against a fork E6 which connects the rod I5 to 'arm 54A; thus when'the force of spring 64 is not overcome there is a 'downward pull on the rod I5 which closes the compass feelers 44 and 445 as far as the position of the pointer 46 will permit (Fig. 15). Further movement of toggle 63 -to the right moves an approximately horizontalfarm 51 upward around its stud 68 onthe forward housing wall. Setting arm links GBR and BSL are pivoted at their lower ends to the free end of arm 6T, andslottedly and rota-tively pinned at their upper ends to lower side extensions of setting arms 52R- and'SZL, respectively, as shown at 'IDR and TBL. Thc'setting arms Yare bell crank levers. both swinging 0n the 4pivot 5I), but as shown in Fig. 4 are in the same plane except at their bearings. so Acannot pass one another. The setting arms are drawn together by suitable-mechanism `52A such asy a c connecting rod with compression spring thereon.

' Straightening the toggle B3, which lowers arm B'I spreads the setting arms.

It, will be recalled that the locking arm '54 (which is wedge-topped as at 54B) is positively lconnected through pull rod I5v to the scissors on the down stroke of the rod, which in turnis governed bythe Vrelation of the compass pointer 46 to the course Set. Consequently .when the toggle 60 is pulled from theextended positionof Fig. 6 to the broken. position of Fig. 7 vandthe leftward movement of keeper. iing'er 53 vclears locking arm 54, allowing. the latterto be moved leitward by spring 64, the end position ofsuch movement depends on whether `the Vessel is on course or how much off and which way. `The setting arms keep on their mutually approaching swing as the pull of rod 62 continues, until first one and then the other is stopped by the locking arm 54. The slotted connections lat 101:?l and 10L allow suilicient independence of movement so that either 52R or 52L, as the case may be, can nish its closing movement after the other stops.

The locking mechanism includes a fixed arcu- -ate rack segment 1I, toothed on upper and lower edges, conveniently located slightly below stationtary segment 4|. Up-nosed pawls 12R and 12L on the respective limit arms rideup the sides of wedge 54B into engagement with bottom notches of rack 1|. These pawls are so shaped that they do notrprevent outward movement of their re- I spective setting arms.

The function of the limit arms is to set the switch arm y40 in position corresponding to that of locking arm 54, in order to initiate the necessary rudder movement. This is accomplished by mechanism shown in detail in Figs. 9 and 10. The switch arm carries a transverse boss 13 on its forward face (using forward inthe sense of towards the bow of the vessel, although away from .the observer1 in Figs. 1 and 5 to 8), to which a pair of inwardly directed down-nosed pawls 14R and 14L are pivoted as best seen in Fig. 9. The noses of these pawls are so shaped as to ride over the upper teeth of rack 1| when the pivot is leading and the tail trailing, but to lock when the tail is leading. That is, 14R will click over the teeth when switch arm 40 moves counterclockwise in Fig. 9 (clockwise in Figs. 5 to 8) but 14L will lock, and vice versa. However, when setting arm 52Rrswings clockwise in Fig.y 9,'a horizontal lip 1ER, Fig.Y 10, rides under the pawl 14R and lifts its nose clear of the rack teeth, as shown in Fig. 10, while an upstanding linger Vpushes against boss 13 to move the arm 40. Opposite movement is accomplished by similar elements correspondingly designatedfL instead of R.

A side crank 40A rigid with the switch arm 40 actuates a linkage BIA to 8|D inclusive, Figs. 1 and 5, which moves a hand 82, Figs. l and 3 against an index 83, thereby indicating the correction being applied, il'l any. The hand may be adjusted as at 84. The linkage is counter- Vweighted at 80. Y

Compass unit, Figs, 1 land 12 t0 15, inclusive v The compass unit `is most conveniently mounted above and oifset from the hand steering wheel 26 on a suitable support such as a vstout tube or pipel4. The unitcan be swung on a vertical axis, set in position for the course to be steered according to a course scale 20| which is bars and is balanced both forv weight and for liquid resistanceby asimilar finger-46" on the opposite end of thesame bars. The motion-of .the finger 46 is limitedby two` opposed rfeeler'leaves 44 belowiand 45 above-,horizontally pivoted. at 2|2 and 21H1 toears2l4and 2|5 respectively,.in side the bowl 204..

As seen .in Figs. 14 and 15 the feelers 44 and 45 arefoverlappingIbell-crank levers having their respective depending arms44 and 45 pivoted to a horizontal link 2I6. The kopposed approximately horizontal edges of the feelers are formed in steps A to GandA to G of varying depth-and length, and itwill be observed, thaty the effective lengths of opposing steps are equal.V The ringer 46, which in thepresent illustration is the north finger, projects between the two feelers.- Itis apparent that the feelers vcan move ltowards one Y another to the least extent when theiinger 46'is between the steps A-AY and to the greatest extent when between the steps GHG. Alternate -closingand opening scissor-like motionis constantly `imparted to the feelers througlrthe pull rod l5 from the continuously rotating control motor I1, as previously described. w The top of the pull rod I5 reaches into the bottom of the compass casingi201 where it is universally jointed as at 2|0, in the axis of rotation of the casing, to the lower end ofa lever 2|9 disposed in a verticalfore-and-aft plane andcur-ved to fit-'between the compass bowl 204and casing 201. :Pivoted intermediate its ends as at 220to the casing 201, this-.lever does not participate in any swinging offthecompass bowl due to a roll orpitch of the ship. Another universal joint 22| connectsthe top of lever 2|9 to onerend of' another first-.class lever 222, vhorizontally.disposed around the edge of the compass; bowl-204and fulcrummed to the gymbal-ring 205, as .at 223.

`The gymbal joint Y224 is hollow to allow passage of a rod 225 into the compass bowl, leakage of alcohol being prevented by axexible sleeve 226. :The rod 225 is pivotally and adjustably connected to the :far end of llever 222, as shown at 221.

. The inner-end ofthe-rod 225 is pinned tothe free end of Va, lever 230hfast to a short vertical shaft 23| in bearings near the edge of the com.'- pass bowl, clearing the swing of the magnet bars 200.' A lower lever below the `magnet bars and hidden by 230 in Fig. liand by 233 in Fig. 12,

connects by a link 232 to the middle of a thirdf class lever 233 having its fulcrum 234 in the bowl opposite 23|and its free end, which is near 23|, vertically pivoted to a link 235 which is fast to the feeler arm connecting link 2|6, I previously described. yA spring 236 constantly pulls lever graduated for full 360 around'the `base of the unitand read againsta stationary variation-scale 202 on themounting |4,'and the unit is secured by a clamp 203. See Figs. l and 12.)4

The compass is of marine type with lthe usual Abowl 204 mounted in a gymbal ring 205 within the casing 201. As ,in ordinary practice there are Yseveral magnet bars 208 carriedby a float 209,

under a hquid-tight glass2l0. .A nger 46 is attached to-'one end of the center pairof magnet 233 counterclockwise, urging the vfeelers to the open position shown in full lines in Fig. l5. The ends of the link 2|6k are horizontallypivoted to the depending arms 44 and 45 of the feelers 44 Yand 45 respectively. Thus movement of link 2I6 `to the right (full lines of Fig. l5) opens thefeelers and movement to the left (dotted lines) closes them. `Consequently,.the down stroke of rod l5 closes the feelers. This down stroke is'caused by ycounterclockwise movement of bell crank lever 60, which also closes the limit switch |53. A preferredV mechanism for the mounting of feeler 44`is shown in Fig. 13.V The mountings vof both lingers are broken awayY in Fig. i4 so as not to hide parts'ofi the linkage 2 Iii-235. The pivot 2|2 is a large-headednlister screw, threaded into the ear 2|4,V lockedV bynut 231, and holding the lfeeler 44 vunderitshead betweenwashers.v The pivot is inserted through a suitable opening 238,

Mtew'ards plugged. The mounting for feeler is a lett-*handed counterpart oi Fig. la;

Biey the action of this' part of the mechaa nlsm is that the teelerg u, 4I are constantly opening and closing', being opened by spring 2li each time the rod i5 is up, which is oflee' at every revolution of crank 6I. When the feelee are open the compass' magnet systei is free to swing. when the feelers close they eaten the rincer l. between one or another UDDOBGd pail of th mi such as ALA and so on, aeeoriilg to the dlrec= tioonal position of the ngel Il, thiii more Ur les! restricting the feeler closing action according to the angle and side the vessel is oi' het course such restriction of ieeler `closing is translated into correction action oh'tlie rudder by the steel: ing notor controls; l Electrical system, rigs. 1. 4, 5, 11 ana 16 w 20,

The preferred specic mechanism of brushes and segments is best seen in Fiss. land 5, and for the most part has been' described; Referring now particularly tu Fig; 11, the brushes and con= tact segments are parte of circuits which operate control relays INR and IIOL for the steering motor I6. In the embodiment herein shown and described the power for the entire s-'ysteni may conveniently be taken from a battery ISL val` though for larger instailationa where the motor Il would ordinarily operate at higher voltage than the relay circuitsi appropriate modifications could be made from the exact circuits shown in Fig. 11. It will be noted that the control motor I1, which runs constantly so long as mechanical steering is used, is not included in Fig; 1l;

The brush track on 'each of the three contact segments comprises a. middle dead Space and a live contact br at each side, reference letter! D (dead), R (right) iid Il (left) added t6' the reference charaeterfor the segment to indi"- eate such divisions. The upper dead space D is' wider than the two lower ones. The division betwe'n right and left IIR and L movable up*- per segments and AIR- 421. are to govern the directions of rudder swing, but. the stationary lower segment is divided only for the purpose of ivi'ng a middle dead space AID.

The wiring diagram of Fig. l1 'shows the ps'i tions of parts when the rudder is anlidships co'- ihciding with central position of segment arm 5I, but the vessel or more off course to the lea as might be caused by wind or other conditions; For convenience of illustration the centl imeia tion of the segments is shown as vertical, al though in the actual mechanism an incline! oentral position gives a more convenient arrare nicht. In Figs. 1l and 16 to Z9 the mumble switch arm l0 and segment arm lll are omitted entirely, the brushes MC, 42C and C are indicated by ai'row heads and a center line CI is shown for reference. The center line is inclined in Figs. 16 to 20 as ln Fig. l and others.

With the vessel 29 off course to the left, the north linger '40 of the compass will be between steps G and G of the feelers, with the iesult that when the pull rod Il moves down the feelers reach maximum closing positin.- This allows the rod to make iis complete downdard movement, swinging looliiingl arm M to etr'ane lett, which results in the switch arm Il being carried to extreme lett, as indicated by' the lille Gf, 1i and le. It will se recalled that une setting of the switch 'arfn Il is through theli'nb';L 'ages which are' actuated by control motor l1 through bell crank 80. The connection includes the spring MA, which'allows crank 6D to com# plete eveiy stroke no matter where the position of compass linger It causes the other elements of the mechanism to stop. 'Thus the springopened limit switch |53 is closed briefly during each cycle, as indicated by the dotted positions of Figs. l and l1.. when closed, current from battery |52 hows along wires I1I through 'switch IN tosegmeiits Ill and AIR. Arm lo now lieing in position G2, current flows through brush MG, wire |80, brush 42C to segment 42B, then through lead HBR to the solenoid coil of a colivehtional control relay ISBR, and returns through line Into thebatte'ry. The circuit through the coil of ISUR causes the coil to draw down its armature IlIIR, closing contacts at IRR and IOCR. Contact I63R completes circuit from HER. to IHR. t'o segment 4BR' and through brush 43C and wires Ill) and III to battery. This circuit maintains current through the coil of relay HDR even after limit switch IBI is opened, thus holding contacts IBCR and Ism closed until the desired cycle is' completed as dc-i scribed below.

'I'he simultaneous closing of contact IBCR completes a circuit from battery |52 through leads Ill, IIIR and I12R to afield coil ISR and the 'armature circuit I 6A of the double field steering motor Ii and thus causes the motor to revolve in the direction to produce right move*- meht of rudder.

This rotation of motor I6 turns shaft 20 (Fig. A2), revolving the steering shaft I2 clockwise through the' worm and gear 2| and 22M'and revo'- lutioil of shaft I8 turhs sprocket 2l. This' movement is transmitted by sprocket chain 23 to pinion 2B, which swings the segment arm 5I leftward. l

Meanwhile the continued revolution of the control motor l1 has' allowed spring 52A tc move rod 62 'leftward straightening the t'og'g'le 53, spreading the setting arms 52B. and 52L, and thus' freeingA the co'iitlol so tha lt can respond t'o the compass indication 'at the next cycle. This' freeing movement is accompanied by a lift of the roel l5 which, simultaneously with the action of' spring 23s, opens the felers and lets the compass magnets' swing. However, the paWlS 'HR and HL einain engaged irl their rack, so holding the switch arm locked until the next closing of the feelers "-41 As the segment arm 5I swings to the left, the contacts 43B and im are moved under the cor; responding locked brushes 43C and I2C until the dead 'spot 43D passes under brush 43C, as shown in Fig. 17. 'Ihis breaks circuit through line IHR., deenergizes the coil of I50R, spring IBIR lifts the armature IGOR and breaks Contact at leien,l tous interrupting the circuit through IHR and stopping the steering motor It. The worm and gear II and 2! having a low enough helik afhgl to be self locking, the steering shaft I! is held from turning by the worm 2l so long as the Worin shaft 20 is stationary. The length of dead ISD is such as to stop the movement of the rudder While the rudder' is still some app'eeial distloe to the right of the amidships position as shown byr the leftward displacement the movable segments from the center line in Fig; 17. This is done to prevent a continual hunting' action 'and to allow a slow adjustment of the rudder when near the amldships position and tlms had a positionl slightly 'oli center to corn'- pensate for 'eil'ects o1 wind, propeller action, etc.,

which mayvcause a continual trend of the vessel to yonejside or another of the desired course.. i

' This slow' adjustment is accomplished as fol'- lows: As the vessel approaches vthe desired course due to previous movements lof the mechanism, dead spot 43D eventually comes under brushV 43C, as already explained. At this time the rudder may be say v" oli amidships. When control motor I1 closes limit switch 453 as previously described, the same circuits are completed as before with the exception of the holding circuit through brush 43C. Therefore the solenoid of relayV ISR is energized only as long as limit switch 53 is held closed by lever 60. Since the control motor closes the limit switch at frequent intervals, a slight jogging action occurs, running the steering motor iB only during the short periods of limit switch closure, and so imparting short corrective movementsl to the rudder unless contact 42C is also on its dead spot 42D. Ifthe segment f 42B. is under the brush this corrective movement 1s to the right, if 4211 is under, the movement is leftward. The length of dead spot 42D is only enough to prevent brush 42C from contacting 42R and 42L simultaneously.

When the compass indicates the vessel to be on course, in which event the step -D-D' on the feelers 44-45 close upon thev pointer 46, the switch arm 4U is central, with brush 4l() on dead spot 4 ID and no current flows to brush 42C, con- :'f

sequently no movement of the steering motor occurs. 1

This sequence has been described for a right rudder action but it is evident-that a similar action occurs for left rudder when contacts 421. and .1.

43L are under their brushes. In this case the relay |50L acts, the various circuits and other elements marked L in Fig. 11 come into play, and

the steering mo-tor I6 is operated through its reverse field IBL. A double field motor has been indicated but a similar result may be `obtained by suitable contacts on othertypes of reversible motors.

Figs. 18, 19 and 20 show action of the electrical controls in other situations thanthose described. In Fig. 18 the position F2 ofthe brushes is that resulting from compass finger 46 being caught between feel'er stepsy F-F, the lrudder being as far rightl as in Fig. 17. The left holding l relay |50L is brought into action, the circuits established being the left counterparts ofthose described as to Fig. 11, energizing the left field ISL of steering motor IS, the result being that the rudder isY moved leftward, and the movable segments are moved toward the center line CL.

In Fig. 19, with rudder amidships the compass 'nger has been caughtY between steps C-C, bringing the brushes to a position C2. The only electrical contacts effective are 4|D-4lL and 42D-42L so that leitward jogging action ensues. Fig. illustrates a situation where there is a. slight right rudder but the compass ringer has been caught between stepsE-E, causing brush position E2, indicating a need to swing the bow slightly to the right. The relation. of brushes and dead spa-ces is the same as in Fig. 17, whichfcauses jgging to the right.

The sensitivity of the steering depends on the length of the feeler steps. For the specific feelers shown in Fig. 15 there is no correction for less than 1 swing oli in either direction; swing oft' course between 1 and 5 tothe right will cause the finger 46 to be caught by steps C-C, and bring arm 43 to the position()2 (as in'vFig. 19); between 5 and 121/2 right, Steps B-B; from 121/2o to 20 right, steps A-A'; correspondingly for swings tothe left; between 1 and 5, E-E- l and position E2' for arm 20 (as in Fig. 20) between`5 and 121/2", F-F and position F'2 for arm 2D (as in Fig. 18); from 121/2D to 20` steps G-G and position G2 (as in Figs. 1 6 andv 17).

My apparatus can be simplified, but at the expense of steadiness of steering, by the limit switch |53, control motor `I'l, segments43R and43lfl brushf43C and the holding circuits, and'fconnecting 42Rfand 42L directly to ISR and IBL, respectively. So simplified'there would of course'be no jogging-action. Movement of the brush v42C' off deadv space'ZD would start the steering motor, and. corrective movement of the motor would bring the dead space back under the brush, thus stoppingthe motor.A

It will be understood that my invention is capable of being modified in forms and arrangement of parts as may be advantageous for varied requirements of size of thevessel on which installed, power available, nature of service conditions it is expectedto meet, and other -factorsl It will be further-understood that the mechanisms and electrical connections and circuits shown and described are preferred but not exclusive forms, and that various modifications thereof may be made without departing from the teaching and principles of my invention. The embodiment shown vand described is therefore intended as `an illustration of 'a preferred form of my'invention'and not as a limitation thereon.

WhatIclaim'is:v v

1. Steering apparatus comprising in combination," a compass, a rudder,` a driving motor for said rudder, switchi'ng'cont'rols for said driving motor, and. a mechanical connection between said compass and saidswitching controls; said mechanical connection comprising intermittently-'actingfeelers responsive to thev direction of said compass, 'an`electrical contact-carrying element responsive to the response'ofsaid feelers, vand another electrical contact-carryingelement responsive 'to the 4position of said rudder.V

2. In an automatic steering mechanism, 1n combination, a. direction-indicating element, a feeler mechanism adapted to make intermittent responsivecon'tact therewith, a steering motor, anda switch mechanism governing 'the action of said motor,` said switch mechanism including a switch arm; connecting elements between said feeler mechanism'and said switch arm whereby to positionsaid switch arm according tosaid responsive'contact; said connecting elements' including switch-arm-setting Ameans adapted vto make intermittent setting contact with said switcharm; and a prime mover causing synchronous intermittent movement of said feeler mechanism and Vsaid switch-arm setting means,

3. In an' automatic steering device in` combination a movable case having therein'a compass, feelers cooperative therewith to determine the compass position, and stops limiting the compass swing tothe area of feeler action; mechanism for intermittently moving said feelers into -po'sitionto stop compass swing and concurrently todetermine'compass direction; a contact-carrying arm movable into successive positions cordesponding to succesive feeler closing positions and means adapted to hold said arm for a-limited time' in each' of said successive positions, a plurality .of contactsegments with respect to vwhich said'co'ntact-carrying arm ismovable; a steering motoriandY a rudder driven thereby, electrical connections'between said rudder and eelt-lino saidsegrnentsfor; moving anzid certa-in segments in accordance lwith movement: arsouree of' electriea'pewer andafplurality et circuits-between said power source andsaid steer inggmotorf, alimit switch actingY upon all `o( said circuitsV eeetivefwhen open tor'prevent .starting of said steering motor; an 1 operative'eennedion between saidffeeier-movingmeehanismandfseid llitsvidtehV effective to closesaid limit` switch mementariy at: thesefeeling acciai: hnlingswitehes im certainlofsendcirclll En! km said lsteering motor rum-nim artterf seid limit' switch. opens; wher-einig,v when` saidv realen eloee arl-movement is initiated in thdsteerim; motor to; alterY the rudderV positionpgk,l to theamount the vessel is ocoursenndwhereba said alteration is continued until return: to caerse;

4;*,Inarr autorisatiey ateei'ins7 mechanism.'A in eombinetionae; cenrpasseunit. a-

a meter-for actuating saidrunits in s. an rudderdrivins I' motor, ami eiectrieal: cinms contreiledibm said' controi'unfor chelatingisaii rudderdrivingf motor; seidA eompass'funit com ming al directiox'mpoimterj a pairfd 'feelerl adnptedito'engage seidmeinter; at-,pei$iens den pendent nthe pointer noemen; seid control unit including ai: swinmablzf lecbima.y adapted: te tls-positioned r`te' Nimmt-1mi# tierrsofsaid-feelers anstagtelei-hevinzmkeee! memberwl'xieh when; mendeds.hdds';said c lacksA ing arm4 toconefsit o( its swine' undfzwhint the toggle is broken allows said: locks'ngl arlll to sling; a: red`l connecting; said; ieelerisfy amel sald lkingcarm; a; spring onsaid: rodadnnted te me sddfrod; in: a direction: tofcheersed feehrs and sillltml tuzswna: saidrflucking am item '.the.' pnsitizniin'which: thekeenen Isolda` ir, Lilagefftrain xcormectinmss :actuating motor; .inaidzitoggle/N and said-f lockknwarmgvanira; spring meistert. withz smid 'f traina admet to bleak: said` toggle'andftherebwfremvefsaid'keeper fromzsaidlnckingmmnthefelvgaisofreeim seid connectiim; rod to= respond: to; its?A sm and therelmm-sairkzfeeezs totem pmitinn and sadr'` leaking; am: te munitions:l corr: to tlxefpeeitiem ofthe ieelers:y

5c In; an: antemmtiev steeriw'mechamsr in canlnaticn: a.: compass# at' contrat: anim, a

mimic' for: sadkfunlsrin I synchrkillt.

as ruderederivim= motor; electrical circula'. een. traded@ by.y said:` control unit fen" oi'ierail'zgt se mdnersdriwingf. motor andv a. visual; indiitot satdfs imita-femmine .a mdf a: pur ot; feelers-:z toy engage said pointer at poeitinm depemientrolr; tu: pder position: saiaicmtrobnmitrimlldint fac-esprimi! leeinngfarm ade/ptedstuzbrmsitienedvaeeerdinx to saidfemagmgpesltimrofsaddleeiera md'a toggle.- haA/inga keeper-member which when, extendedholdsfsaidlocking om:f sier-of its mgl-and wheny the: toggieA isbrobmalhnssdd locking: arm'vtov-swmg; a red" cemneettnagsaid feelers and said1Iockingv-'arm; a: sprinzt'onsdd rod adapted to move: saidl'redriin'z aA dixectinnite cioee saidV feeers and* sizleixlilaineomly` tof sm'nz said' inciting-arm away from the-pesitmznyhich the keeper hoidsit; linkage train: connecting said'aetuaairrg motor; said toggle, andlsaid lacie li'igf'arrir, anda suing-associated with-.saidlm'b agetrainadapted to breaiesad-toggle' and'theef.- byremove said keeper from said locking am, thereby also'lfreerng fsad connecting K rod to: re# sporrdto its spring and thereby-I move said-*fakes tofeelingA position' and- `said @locking peattion corresponding to the positionof the feelers; said control unit also including aswitcharm for switching said circuits andsetting arms for bringingsaidrswitcharmrto a.. position, opposite said lockingarm and locked thereby; said visual indieator including a.- pointer andal linkage. connecting said pointer-with said` switch arm.

GcAr, direction-responsive control devicecom, psinginfcombinationa switch arm-With a.plu. ralityro brushes carried thereby, a. plurality of fixed eledsrieal contacts over which certain of .said brushes-'are adapted to lbe carried by movement o said armganotherplurality ofelectrical contactstmd means-.formovng same asv aunit with respecty tootherl brushes carried' by-'said switch arm; and means for moving said arm .to a prede-r terminedY position, said means comprising two settingamas, .elementsfadapted to engage each of said-setting arms #independently with said switch arm to-move the^1atter only1 in= that. direction whichcarries saidsettingfarmstoward one arl;-v other; and a-directin-responsive eleanent-adapta edto lockisaid settingarmsindividuallyagainst furthe! inward movementi whereby said switch arm is positioned correspondingly tol-saiddirec tion-responsive element.

7. A direetiom-responsive controlldevicecomprising, in lcombination racfeeller.- imitV intermittent,- ly` resfionsifve: to directional changes, a motor adaptedito cause appropriateresponsesrto such changes,y meansfzfor:l controlling. said motor; said controlling means comprising a switch-arm, a', locking, arm; akieeper. arm; andfmcchanical conneetionsfrespectiveiy-fbetween said locking arm andsaid-keeper arm.,- md between'said locking arrnI and :said f; feeler1V unit; whereby said keeper arm, intermilitentlyv releases saidloclrirg` arm and wflvlerebyA during: suairreieaseV said-locking arm vassnaiesra position `determined zlay-said -feeier unit, anisaidfsmiteh amalis positioned-correspandinglyto said: lockingfarm,

8i A- direction-responsive control device com prising in combination a feeler unit intermittently responsive-:to directional changes; a motor @adaptedy to :cerise appropriate responses. to such chansesand meamfforicontrollirrg said motor: saridracontrolling means4 comprising asWitch zarm withfa pl-iiredityfci brushesfvcarriedthereby, a directionhresponsive leclxingfarm;` a keeper' arm, and mechanical connections-respectively between saidilokingarmfand saidkeeper arm, andbetweenY said loakingarm and' said ieeler: unit; whereby said arm intermittently releases saidflocking arm andwhereby during-'Suchmelease said lockingA` arm -assunies` a positiondetermined by saidfeeler unit'and said switch arm is correspondingly to saidlocking arm; said meansvformovingfsaid :switch arm comprisiingtwofsettixg arms', elementsadapted to engage cachot :said setting armsindependently with said switch arm tomovethe latter only in that direc'- ticn which fcarries said setting:y arms ltowardsonc another; said locking arm being-adapted to vlock said setting` arms individually againstfurther'inwardmovement; a= plurality of xed electrical contacts .overrwhich certain'of.- said brushes are adapted to be carried by movementofsaidfarm; another pluralityvof electrical .contactsand means .for movingsame'as a unit with respect to other brushescarried by said switch arm-,- and a plurality of circuits for driving' said motor, said brushes andxed and'movablecontacts being included .in said circuits;

9. In an automatic steering mechanism acompaes unitcomprisingjn `combination a compass,

a iinger carried by the needle system of said compass, feelers alongside the space wherein said nger can swing, mechanism causing said feelers Y said inger can swing, feelers alongside said space,

mechanism causing said feelers to make contact with said iinger at intervals of time, and edges of varying depth on said feelers adapted to terminate said contacting movement in accordance with the position of said finger.

l1. In an automatic steering system a compass unit comprising in combination a compass, a nger carried by the needle system of said compass, a pair of opposed feelers above and below the path of said iinger, means for imparting intermittent scissors action to said feelers to close upon said finger, stepped opposed edges on said feelers, said steps being of diiierent depths whereby the extent of closing of said feelers is determined by the position of said finger at time of closing.

12. In an automatic steering system a compass unit comprising in combination a compass, a linger carried by the needle system ofsaid compass, stops limiting the swing of said finger to a deiinite space, a pair of opposed feelers above and below said space, means for imparting intermittent scissors action to said feelers to close upon said finger, stepped opposed edges on said feelers, said steps being of diierent depths whereby the extent of closing of said feelers is determined by the position of said iinger at time of closing.

13. Automatic steering apparatus comprising in combination a compass, means for determining the indication of said compass, a rudder, a steering motor for actuating said rudder, and control means for said steering motor, said control means comprising two members movable relative to one another, means for moving one member according to compass indication and the other according to rudder position, electrical contact elements on each member mutually connectable to close a directional circuit to said steering motor, a dead space separating said contact elements on said rudder-responsive member, thereby dividing the contact elements thereon into sections one of which, when in circuit, drives said steering motor in one direction and the other of which, when in circuit, drives it in the opposite direction.

14. An automatic steering device comprising in combination a compass, a motor, a rudder driven thereby, a source of power, and a switching mechanism, mechanical connections from said compass to said switching mechanism responsive to the direction of vessel heading, said switching mechanism comprising a limit switch effective asto all circuits, two holding circuits selectively operable for by-passing said limit switch, a driving circuit controlled by each of said holding circuits to drive said motor forward or backward, a stationary contact, a contact movable according to rudder movement, and electrical connections between said stationary and movable contacts which are selectively set according to direction of vessel heading.

15. In an automatic steering' apparatus a steering motor and circuits for controlling said motor to run either forward or backward, said circuits comprising a plurality of brushes and a movable arm carrying them, iixed contact segments over which one of said brushes moves, and other contact segments over which the other brushes move, said other segments being iixed to a carrying arm, mechanical connections to a direction-responsive device for moving said brush-carrying arm to a position determined by such device, and mechanical connections to the steering motor for lmoving said segment-carrying arm correspondingly to those movements of said steering motor which are occasion-ed by the setting of said brush-carrying arm.

NEIL T. SAWDEY. 

